Supplement to "Nature" December 23, 1922 



Pasteur. 



By Stephen Paget. 



OF late years it lias become the fashion to limit the 

 name of preventive medicine to the immunisa- 

 tion of ourselves or of animals against infection. With 

 the one exception of vaccination against smallpox, all 

 methods of immunisation are founded on Pasteur's work. 

 The contrast is remarkable between Jenner's discovery 

 and Pasteur's many discoveries. Jenner, ages back, 

 made a great dis- 

 covery : but there 

 he stopped. Pasteur 

 not only made dis- 

 coveries : he made 

 discoverers. We are 

 so accustomed now- 

 adays to the new 

 learning which he 

 brought into the 

 world that we are in 

 danger of forgetting 

 the original wonder 

 of it : the power to 

 identify, isolate, 

 cultivate, and 

 handle, outside the 

 living body, this or 

 that disease : to 

 hold in a test-tube 

 the actual cause, the 

 thing itself, the very 

 stuff of disease, 

 growing under our 

 eyes. That is the 

 tragedy of Semmel- 

 weiss : he worked 

 out the truth about 

 puerperal fever, but 

 he could not demon- 

 strate the germs of 

 it : therefore he 



Fig. 1.— Pas 



was contradicted, 

 bullied, hounded down, driven mad, and died insane 

 in 1865. Pasteur, in 1878, in a discussion at the 

 Academie de Medecine on puerperal fever, when 

 one of the speakers railed at Streptococcus as a non- 

 reality, forthwith drew Streptococcus on the black- 

 board, saying, " Tenez, void sa figure." 



After all, it is impossible, in Pasteur's work and its 

 influences, to separate preventive medicine from 

 curative medicine. Long before Pasteur died every 

 country was at work on his lines. We can take some 



dates in his life : but he was always living in the work 

 of lesser men whom he inspired. The dates in his life 

 are as follows, fn 1842, fortified by the virtues of 

 home-love, and by the courage of youth, he went to 

 Paris : entered the Ecole Normale in 1843 : worked 

 under Dumas and Biot at chemistry, and at chemistry 

 only : and in 1848 he solved the problem of the different 

 forms of tartaric 

 acid. For this 

 reason he has been 

 called the founder 

 of stereo-chemistry. 

 His pursuit of the 

 tartrates led him 

 straight to the prac- 

 tical study of the 

 processes of brew- 

 ing, distilling, vine- 

 gar - making, and 

 wine - making. By 

 this work on fer- 

 mentation, Huxley 

 said of him that he 

 saved France more 

 than enough to pay 

 the indemnity of 

 the Franco-German 

 War. In 1857 came 

 his paper at the 

 Lille Scientific 

 Society on Bacterium 

 lactis : he had iso- 

 lated this ferment,^ 

 had experimented 

 with it : and this 

 " inoculation " of 

 milk with a culture 

 of germs was the 

 beginning of all 

 bacteriology. 



From 1865 to 1870, without giving up his work on 

 ferments, Pasteur set himself, at Alais, to investigate 

 the silkworm disease, which was wrecking the silk- 

 industry of France and other countries. He found not 

 one disease but two — pibrine and flacherie. The story 

 of his final triumph, after infinite difficulties, in this 

 investigation is marvellous : it is told in his " Etudes 

 sur les maladies des vers a soie." He used to commend 

 this hook to students to guide them in the principles of 

 their work. 



